Most people are unaware of exactly how many types of terrain there are in the Warhammer 40k main rulebook. They seem to forget that there is a plethroa of other types besides hills, ruins, and area terrain. Let's review a couple of the lesser known ones....
Ammunition Dump: Any model within 12" of an ammunition dump can reroll to shooting to hit rolls of 1 and provides a 5+ cover save.
Comms relay: Provides a 5+ cover save and let's a player with a model within 2" inches reroll reserve rolls.
Fuel Reserve: Provides a 5+ save. After each succesful save roll a dice. On a roll of one center the large blast marker over the model making the save. On a 1 place the large blast marker over the model making the save. All models touched by the blast suffer a S3 AP- hit.... the fuel barrels exploded!
Imperial Statuary: Armies of the Imperium gain the fearless special rule while within 2". If you're behind it, you gain a 3+ cover save.
These are just a few of the terrain types that a rarely used that may spice up your game... check out pages 104-105 for more!
Most people don't seem to understand how skyfire works when it comes to shooting with fliers. Typically people like to shoot them at anything without regard whether their target is a flier or not. At the start of the shooting phase, fliers must declare if they are going to use the skyfire rule. If they start shooting without saying anything and then they require 6's to hit fliers, just like most everybody else!